Climatological Data
Copyright © 1996-2010 STORMFAX, Inc.
Weather in Chatham at this hour !
Weather in Chatham the past 48 hours !
Chatham Harbor
The Chatham Squire WebCam
Chatham, MA
NWS/1971-2000 
AVERAGE TEMPERATURE
| Year | Jan | Feb | Mar | Apr | May | June | July | Aug | Sep | Oct | Nov | Dec |
| 49.4 °F | 30.9 | 31.0 | 36.8 | 44.8 | 53.5 | 62.0 | 68.3 | 68.0 | 62.8 | 53.5 | 45.0 | 36.2 |
AVERAGE HIGH TEMPERATURE
| Year | Jan | Feb | Mar | Apr | May | June | July | Aug | Sep | Oct | Nov | Dec |
| 55.5 °F | 37.7 | 37.7 | 42.8 | 50.4 | 59.1 | 68.0 | 74.6 | 74.2 | 68.7 | 59.7 | 50.9 | 42.6 |
AVERAGE LOW TEMPERATURE
| Year | Jan | Feb | Mar | Apr | May | June | July | Aug | Sep | Oct | Nov | Dec |
| 43.2 °F | 24.0 | 24.3 | 30.7 | 39.1 | 47.9 | 56.0 | 61.9 | 61.8 | 56.9 | 47.2 | 39.1 | 29.7 |
HIGHEST RECORDED TEMPERATURE (All-Time)
| Ever | Jan | Feb | Mar | Apr | May | June | July | Aug | Sep | Oct | Nov | Dec |
| 97 °F | 59 | 59 | 65 | 79 | 83 | 97 | 94 | 93 | 89 | 82 | 74 | 65 |
LOWEST RECORDED TEMPERATURE (All-Time)
| Ever | Jan | Feb | Mar | Apr | May | June | July | Aug | Sep | Oct | Nov | Dec |
| -9 °F | -7 | -9 | 3 | 19 | 31 | 41 | 50 | 51 | 36 | 29 | 15 | -2 |
MEAN NUMBER OF DAYS Below 32°F
| Total | Jan | Feb | Mar | Apr | May | June | July | Aug | Sep | Oct | Nov | Dec |
| 101 days | 25 | 23 | 19 | 4 | 0 | 0 | 0 | 0 | 0 | 1 | 9 | 21 |
NORMAL HEATING DEGREE DAYS
| Total | Jan | Feb | Mar | Apr | May | June | July | Aug | Sep | Oct | Nov | Dec |
| 5931 | 1058 | 952 | 875 | 608 | 357 | 110 | 16 | 12 | 89 | 359 | 601 | 894 |
NORMAL COOLING DEGREE DAYS
| Total | Jan | Feb | Mar | Apr | May | June | July | Aug | Sep | Oct | Nov | Dec |
| 265 | 0 | 0 | 0 | 0 | 0 | 20 | 116 | 104 | 24 | 1 | 0 | 0 |
AVERAGE PRECIPITATION (Inches)
| Total | Jan | Feb | Mar | Apr | May | June | July | Aug | Sep | Oct | Nov | Dec |
| 46.71" | 4.23 | 3.98 | 4.14 | 3.95 | 3.71 | 3.44 | 3.38 | 3.33 | 3.91 | 4.12 | 3.89 | 4.63 |
AVERAGE DAYS of PRECIPITATION
| Total | Jan | Feb | Mar | Apr | May | June | July | Aug | Sep | Oct | Nov | Dec |
| 67 days | 7 | 8 | 7 | 7 | 5 | 4 | 5 | 7 | 5 | 4 | 6 | 7 |
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